Three species of marine mammal encountered during second research expedition of 2023
our SECOND research expedition of 2023 left tobermory for a SEVEN-day survey monitoring THE HEBRIDEAN MARINE ENVIRONMENT on board silurian - our research vessel. THINGS GOT OFF TO A ROLLY START BUT CALM SEAS PREVAILED ALLOWING THE GROUP TO COLLECT VITAL VISUAL AND ACOUSTIC DATA. the volunteer team on board recALL their expedition…
DAY 1
Volunteers Alun, Anaïs, Clara, Eileen, Georgie and Vic joined skipper Alan, first mate Jake, science officer Hannah, and 4th crew Fergus at the top of the pontoons excited for the research survey ahead. After getting familiar with Silurian and making the cabins feel like home, the evening was packed full of safety information as well as an introduction to HWDT. Just as Hannah was about to begin the species ID presentation, Fergus shouted SIGHTING, and right on cue, 5 harbour porpoises surfaced close to the boat. Everyone jumped up on deck for fantastic views of the porpoise foraging in the bay, ID-able by their triangular dorsal fin. A cracking first spot of the trip and we hadn’t even left the bay! The rest of the evening was spent learning more about marine species we may see in the Hebrides with Hannah hoping other species might surface on demand. We tucked into a fantastic veggie spag bol made by Fergus and headed to bed, ready for our first full day onboard Silurian tomorrow.
DAY 2
We awoke to beautiful weather in Tobermory Bay with the sun shining on the different coloured houses on the main street. The morning was filled with training presentations on surveying protocol and acoustics to ensure data collected throughout the week would be standardised, even practising our ‘SIGHTING’ distances with points of interest in the harbour.
Setting sail towards the Isle of Coll, we hoped to top our amazing sighting of 5 harbour porpoises (and a wee otter) from the previous evening but settled for 65 creel sightings instead and some choppy seas. Getting used to moving around Silurian whilst wearing our fladen suits and the different roles for collecting data kept us busy for the rest of the day. Our shelter for the night is Loch Na Droma Buidhe (or Drumbuie) where we’ve anchored for the evening. Vic and Eileen are cooking tonight followed by a presentation on how to ID different birds and boats! Everyone is looking forward to tomorrow’s survey with at least one marine mammal, hopefully!
DAY 3
Yesterday seemed to be the calm before the storm, as we sheltered in Drumbuie from the incoming front from the Atlantic. A slightly delayed start to allow the weather to calm we were soon underway with a wee sail much to the delight of everyone onboard. Soon the conditions forced us to turn on the engine and motor down the Sound of Mull with very wet and wild conditions on the mast! With the weather conditions worsening and a few onboard starting to feel unwell the decision was made to head back to the safety of Tobermory Harbour and wait with fingers crossed for the weather to ease. Hunkered down in Silurian we chatted, cooked, cleaned, and ate plenty of snacks!
After an updated weather forecast it became clear that the rain and wind were not going to stop and that we would be stormbound for the rest of the day. Science turned entertainment officer Hannah decided that we were going to undertake a quiz, the idea of which scared a few of us and we were right! First mate Jake won with a very respectable 19/34 however it has highlighted that we must improve our Hebridean knowledge, particularly its lighthouses!
DAY 4
Today was epic! Up bright and early, the team were ready to be ‘on effort’ as soon as Hannah and Skipper Alan allowed eager to make up lost survey time. Dropping the mooring we motored out of Tobermory and around Calve Island. The plan was to head South and stay ‘on effort’ for as long as we possibly could hoping to spot a few marine mammals along the way.
The sun was shining, and the sea was like glass, with little swell it was almost excellent sighting conditions! Surveying the Sound of Mull was a dream with three grey seals, one common seal and six harbour porpoises spotted as we headed towards Lismore whilst also admiring the fantastic views of the Isle of Mull and Morvern. It was a good job we were so well rested as there were also plenty of creels and 3 pieces of rubbish to be relayed and inputted to the science station. Nearing Oban, the increase in vessel traffic highlighted the importance of our acoustic survey work with volunteers identifying the sound of different vessels as well as the chain of cardinal buoys from the hydrophone.
We continued to motor South and were treated to epic views of the Paps of Jura in the distance. Surprisingly most of our sightings occurred in the Sound of Mull as we only spotted creels and two unidentified seals for the remaining of the day. However, that did not dampen our spirits as we collected nine and half hours’ worth of visual and acoustic data, an incredible effort from the volunteers and crew! Our anchorage this evening is on the east coast of Oronosay where we were able to go ashore and have a wee explore! No pubs, but a few puffins and oyster catchers. This evening we are addressing the Haggis, to celebrate a wonderful day onboard Silurian.
DAY 5
It all looked a bit worrying to start but we completed another epic day of data collection surveying for nine! We woke to the wind howling around the boat, but Alan assured us that a high-pressure system was moving in and that blue skies were forecast, and he was right! We had cracking weather all day with jackets being stripped off in the afternoon sun whilst motoring up the south side of Mull. The fantastic conditions enabled Alan and Jake to hoist the sails, turn off the engine and sail at 6 knots – a delight for everyone onboard enjoying the sound of the engine switched off. Dedicated acoustic surveys were filled with the sound of snapping shrimp without the hum of the engine interfering.
Despite almost excellent sighting conditions, sadly no whales or dolphins were spotted today. All hope was lost for a cetacean sighting as we made a course change for our anchorage this evening until Hannah spotted 1 harbour porpoise just before we were to come off effort – result! Tonight, we have anchored off the island of Lismore in a stunning spot, buzzards flying overheard, eider ducks, and some more oystercatchers. We are enjoying soaking up the sun and scenery before dinner tonight.
DAY 7
Treated to another beautiful morning wake up, we quickly lifted anchor and were straight on effort calling in an extensive bevvy of creels. Heading towards Tobermory, it was warm in the sun with crew peeling off layers but as soon as anyone was in the shade it was cold, with the wind coming off the snow-capped hills.
Just a few sightings today – two grey seal sightings, one unidentified seal sighting and a harbour porpoise aside from the multiple creels. Bird life was limited with mostly gulls, but the calm seas and beautiful scenery heading back to Tobermory made up for a rather quiet morning. The glamour of the day was provided by multiple flybys by a drone filming for HWDT. Hannah gave us a heads up to be ‘on it’ but let’s face it we’re the best volunteers she’s had, and we were already on it 100%!! After the drone whizzed around the boat, conditions were favourable for people to climb up to the crow’s nest and take in the views. Fergus and Clara were the only people who took up the offer and both made clambering up the mast look professional.
Soon we saw the multi-coloured houses of home and knew our time on Silurian was almost over. It’s been a super EFFORT with a bit of everything weatherwise with a fantastic team. After a thorough clean and tidy of the boat, we headed ashore for our evening meal to celebrate the week at sea followed by a hectic game of pass the pigs in the pub!
Across 7 days, the group surveyed 151nm of Hebridean waters encountering 3 different species of marine mammals with 20 sightings and 26 hours of acoustic data recorded.
A big thank you to the fantastic team of volunteer citizen scientists ALUN, CARA, eILEEN, ANAIS, VIC and GEORGIEwho participated in the expedition. Every data point in our vast database is collected by you - members of the public!
Image showing the track line of area surveyed and sightings during HWDT02 2023.
THANKS ALSO TO NATURESCOT FOR SUPPORTING THE DATA COLLECTION ON BOARD SILURIAN.